Engine

ABSTRACT

An internal combustion engine in which a power generating cylinder has a piston drivingly coupled with a piston in a combustible fluid compressing cylinder by means of gears connected with a power delivery shaft and which are adjustable to vary the timed operating relationship at which the pistons reach their respective dead center positions, the compressing cylinder having a valve controlled inlet for a combustible fluid which is precompressed therein and delivered through an interconnecting valve controlled passage to the power generating cylinder into the space above the piston therein where it is confined under pressure and ignited after the piston in the power generating cylinder has passed and is moving away from its dead center position. Electrically energizable solenoids are provided for operating the respective valves in timed relationship as determined by timing switching means synchronized with the rotation of the power delivery shaft.

United States Patent Stratton [451 July 11, 1972 [54] ENGINE 1,679,1587/1928 French............................123/90.1l X

[72] Inventor: Cleo C. Stratum, 2123 Kern St., San

Bemardino, Calif. 92405 [22] Filed: July 2, 1970 [21] Appl. No.1 51,820

[52] US. Cl. ..l23/70 R, 123/9011, 123/70 V [5|] Int. ..F02b 13/22 [58]Field otSenrch123/7O R, 70 V, 68, 90111,

Primary Examinerwendell E. Burns Auorney-Whann & McManigal 5 7] ABSTRACTAn internal combustion engine in which a power generating cylinder has apiston drivingly coupled with a piston in a combustible fluidcompressing cylinder by means of gears connected with a power deliveryshaft and which are adjustable to vary the timed operating relationshipat which the pistons reach their respective dead center positions, thecompressing cylinder having a valve controlled inlet for a combustiblefluid which is precompressed therein and delivered through aninterconnecting valve controlled passage to the power generatingcylinder into the space above the piston therein where it is confinedunder pressure and ignited after the piston in the power generatingcylinder has passed and is moving away from its dead center position.Electrically energizable solenoids are provided for operating therespective valves in timed relationship as determined by timingswitching means synchronized with the rotation of the power deliveryshaft.

4 Claims, 3 Drawing Figures ENGINE BACKGROUND OF THE INVENTION Thepresent invention relates to power generating apparatus, namely, aninternal combustion engine.

Basically, the inherent relatively low efficiency of internal combustionengines has long been realized, and efforts are continually being madeto improve the efficiency of conversion of the available fuel energyinto usable mechanical power at the output shaft of the engine. Theseimprovements have been directed to diverse objectives, and as a resultmuch progress has been made. For example, a great deal of work has beendone with respect to the design of the head end of the cylinder, and topof the piston with a view to improving combustion and increasing thepressure of the fuel mixture at the time of ignition. These improvementswere closely allied with the developments of better fuels which wouldpermit the use of higher compressions.

Another approach began with the discovery that long stroke engines wereinefficient due to the quick loss of pressure when the pressure of thegas was suddenly released by the downward movement of the piston. Whilea tremendous pressure was produced on the top of the piston at the timeof ignition, which was at the time when the piston was close to its deadcenter position, this high pressure was not available during theportions of the crank movement in which the mechanical leverage would bethe greatest. As a result of this discovery, the short stroke high speedinternal combustion engine was developed and gained favor over the longstroke slower speed engines. in this new development, a greater amountof the potentially available power could be utilized by having a greaternumber of very short power pulses.

In considering the improvements which have been made, in eluding theimprovements noted above, it becomes apparent that these improvementshave not eliminated a major and important source of inefficiency whichresults from the utilization of a firing point substantially at the deadcenter position of the piston. While it has been found that some gain inpower will be obtained by advancing the ignition point slightly ahead ofthe dead center position, this gain in efficiency is costly for thereason that the forces applied to the piston are at a point of zero orlow crank leverage. These forces are accordingly applied directlyagainst the crank shaft at a time when they are substantiallyineffective to produce shaft rotation.

Another observed source of inefficiency results from the necessity ofhaving to utilize two valves in four-cycle engines. The size of thevalves is thus restricted, and to overcome this problem superchargerswere used to force the mixture through the valve openings. Further, inconventional fourcycle and two-cycle engines, inefficiency results dueto the use of the same chamber for combustion, intake and compression.For example, the intake of combustible mixture from the carburetorenters the heated combustion chamber, and as the mixture heats up itexpands. The pressure within the chamber quickly equalizes the admissionpressure so that a lesser quantity of the entering mixture will bereceived as a potential source of power. Accordingly, the hotter theengine runs the less will be its efficiency.

The engine of the present invention is so designed as to overcome andimprove those areas of inefficiency in the conventionally known engines,and including those areas which have been specifically indicated above.Briefly, this is accomplished by providing a pair of cylinders havingpistons coupled with a power delivery shaft, and arranged so that thecombustible fluid will be compressed in one cylinder and delivered underpressure to the other cylinder after the piston therein has moved awayfrom its dead center position, ignition of the fluid taking place at atime when the crank leverage is approaching maximum, rather than at atime when the leverage is zero or at a low value. Single valves areutilized in the cylinders, thus permitting the use of valves which arerelatively unrestricted as to size and may approach the diameter of thecylinder, thus enabling rapid flow through the valved passages.

In my disclosed improvement, the combustible fuel mixture enters arelatively cool power cylinder, and even though operating temperaturesmay be above normal, the fuel will be forced into it under a pressurewhich will assure a full power charge. Transfer of the fuel from onecylinder to the other provides for increased and better vaporization.Moreover, since the pistons reach dead center position at differenttimes, the angular relationship is such that the crank leverage on thepower piston will be increasing at the same time that the leverage withrespect to the compression piston is decreasing so that the power neededto compress the charge at the greatest point of pressure will besubstantially cancelled. Since ignition takes place after the powerpiston passes dead center position, backfire or backward running isprevented. The engine operates with a minimum of vibration.

SUMMARY OF THE INVENTION The present invention relates generally topower generating apparatus, and is more particularly concerned withimprovements in engines of the internal combustion type.

It is one object of the herein described invention to provide aninternal combustion engine having improved operating efiiciency, highpower delivery, which is substantially free of vibration, and which willnot kick or tend to run in a reverse direction when starting.

A further object is to provide an improved internal combustion enginehaving reciprocable pistons, wherein a combustible fuel mixture will beignited while confined under high pressure, and after the piston hasmoved away from its dead center position.

A further object is to provide in an internal combustion engine of thereciprocable piston type a power generating cylinder and a compressingcylinder, and wherein the piston of the power generating cylinder iscoupled with the piston of the compressing cylinder through a powerfeedback connection.

Another object is to provide an internal combustion engine wherein acombustible fluid mixture is admitted to the space above the piston, andin which the ignition is timed to occur after the piston has passed itsdead center position and during which the angle of the crank is such asto provide high leverage.

Still another object is to provide in such an engine two interconnectedpistons coupled with a single power delivery shaft, one of the pistonsbeing in a cylinder of relatively large diameter provided with a singleintake valve and operating to compress a combustible fluid for deliveryto the cylinder of the other piston which is of smaller diameter forpower generation, this cylinder having a single exhaust valve; whichoperates at high efficiency and provides better vaporization of thecombustible fluid than is possible with a single cylinder type engine.

It is also an object to provide an internal combustion engine whichmakes use of interconnected cylinders having cooperatively associatedpistons connected with separate crank shafts, these crank shafts beinginterconnected by gearing which permits quick change of the timedrelationship of piston movements and consequent change of compressionratios to suit operation with different types of fuels.

Yet another object resides in the provision of means for varying theamount of intake combustion fluid in accordance with changes in ambientatmospheric pressure, as a safeguard against excessive cylinderpressures which could cause damage.

Further objects of the invention will be brought out in the followingpart of the specification, wherein detailed description is for thepurpose of fully disclosing the invention without placing limitationsthereon.

BRIEF DESCRIPTION OF THE DRAWINGS Referring to the accompanyingdrawings, which are for illustrative purposes only:

FIG. I is an elevational view, partly in section, illustrating theoperative relationship of the component parts of the engine embodyingthe present invention, and including schematic disclosure of timingmeans for the valves and ignition components;

FIG. 2 is a top view of a butterfly valve combustible mixture control asutilized with the engine, with variable atmospheric pressure adjustingmeans; and

FIG. 3 is a side view of the same.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now more specificallyto the drawings, for illustrative purposes there is shown in FIG. I aninternal combustion engine constructed with a suitable casing orhousing, as generally indicated at 10, and which may vary depending upondifferent installations. For example, the casing may be arranged forwater cooling or air cooling. Likewise, the disposition of the parts mayvary as to configuration and dimensions, while basically conforming tothe broad concepts of the present invention. As shown in FIG. I, thecasing is constructed to provide a crank case portion ll having acylinder block section I2 secured thereto as by bolts I3, this sectionhaving external fins 14 providing the necessary heat radiating surfacesto accommodate the engine for air cooling. Above the cylinder block,there is provided a head section I which is removably secured as byanchor bolts 16.

The engine of the present invention differs from conventional two-cycleand four-cycle engines in which each cylinder module is composed of asingle cylinder and piston. In the present invention, instead ofutilizing a single cylinder for combustion, intake and compression, themodule utilizes two cylinders and associated pistons to perform the samefunctions as the one cylinder of conventional engines. Of course, asingle engine may comprise several of the two-cylinder modules. Morespecifically, as shown in FIG. I, the cylinder block I2 is constructedto provide a first cylinder cavity 17 and adjacent second cylindercavity I8 which are transversely aligned. Associated with the cylinderI7 is a reciprocably mounted piston 19 of conventional construction,this piston being pivotally connected with one end of a connecting rod20 by means of the usual wrist pin 21. The other end of the connectingrod 20 is connected with a crank pin 22 carried by a disc-gear 23removably retained by a securing nut 24 on a power delivery shaft 25mounted in appropriate bearings (not shown) in the crank case section.

In a similar manner, the cylinder 18 has reciprocably mounted therein apiston 26 which is secured to one end of connecting rod 27 by means ofwrist pin 28, the other end of the connecting rod being similarlyconnected with a crank pin 29 carried by a disc-gear 30 removablymounted on a shaft 31 by nut 32. This shaft is also supported onsuitable bearings (not shown) in the crank case section. The gears 23and 30 are shown as being of similar diameter and as having intermeshingteeth. As thus drivingly connected, the shafts 25 and 3! will at alltimes rotate in opposite directions, and by changing the engagedcircumferential points of the respective gears, the timed relationshipof the crank pins 22 and 29 may be varied so that the respective pistonswill occupy different axial positions at any given time within theirassociated cylinders. As arranged in the illustration, the piston I9will be moving away from its dead center position at the top of itscylinder, when the piston 26 is moving towards its dead center position.The relative angular relationship of the crank pins 22 and 29 may bevaried, and for purposes of illustration the crank pin 22 is shown ashaving a leading angle of substantially 45 with respect to the crank pin29. Thus, when the piston 26 is at its top dead center position, thepiston I9 is moving away from its dead center position on its powerstroke.

It is one of the features of the present invention that one of thepistons, in this case piston 19, is utilized as the power generatingpiston, while the other piston 26 is utilized as a compressor piston forthe fluid mixture. For such operations it has been found desirable toconstruct the compressor piston 26 of greater diameter than the pistonI9.

The power cylinder 17 is provided with a single exhaust valve 33 whichis positioned in a recess 34 of the head block section so as to permitthe use of small clearance between the cylinder end and the upper end ofthe piston, when the piston is in dead center position. The valve 33 hasa conventional stem 35 which is reciprocably supported in the headsection IS and at its outer end has a shoulder 36 forming an abutmentfor one end of a compression spring 37 having its other end engaged withthe top of the head section. The spring 37 thus acts to normally movethe valve 33 to a closed position For opening the valve, an electricallyenergizable solenoid 38 is operatively connected with the stem 35 in awell known conventional manner. In the open position of the valve 33,the upper end of cylinder I7 is connected with an exhaust port passage39 leading to an exhaust connection 40. As an aid in exhausting wastegases from the cylinder 17, after ignition, there is also provided anexhaust port 4i which is controlled by the piston 19 in such a mannerthat when the piston reaches the lower limit of its travel in thecylinder I7, port 4I will be open.

In a similar manner, the upper end of cylinder 18 is provided with asingle inlet valve 42 which is mounted within a recess 43, this valvehaving a stem 44, a shoulder 45, compression spring 46, and solenoid 47.In the open position of the valve 42, the upper end of the cylinder I8is connected with an intake port passage 48 which leads to an inletconnection 49. This inlet connection is connected with a carburetor orother means for providing a source of combustible fluid (not shown). Forcontrolling the flow of combustible fluid to the cylinder 18, suitablecontrol means such as a butterfly valve 50 of conventional constructionmay be provided. Normally provided throttle controls for changing theposition of the butterfly valve may be used. However, since it ispossible in the engine of the present invention to obtain pressures atlow altitudes which could damage the engine, means are provided forregulating the extent of opening of the butterfly valve in accordancewith changes in the ambient atmospheric pressure. At low altitudes, thebutterfly opening will be restricted, whereas at the higher altitudesthe limit of opening will be greater. For such purpose, there isprovided an aneroid as sembly which includes a bellows 52 which isanchored at one end to a bracket 53, and connected at its other end toan actuating rod 54, the outer end of this rod being provided with ahook 55 which extends over an arm 56. The arm 56 is con nected with thebutterfly valve and assumes a position corresponding thereto. Dependingupon the position of the hook 55, the opening limit of the valve will beestablished, while still permitting free closing movement of the valvefrom this limit position.

In order to conduct compressed combustible fluid from the compressingcylinder 18 to the power cylinder I7, the top ends of the cylinders areinterconnected by a flow passage 57 which is controlled by a valvemember 58 in the form of a solid rod, and which is supported forreciprocable movement within a cylindrical bore 59 provided in thecylinder block section body between the cylinders 17 and I8. The valvemember is movable to a position closing the flow passage 57, and to avalve open position wherein a transverse passage 60 in the valve memberwill be aligned with the passage 57. The lowermost end of the bore 59opens into the interior of the crank case so that the valve partsreceive splash lubrication from the crank case. The valve member 58 isnormally urged to a closed position by means of a compression springbelow the valve member, this spring 61 having one end bearing againstthe valve member and its other end bearing against the screen filter 62at the lower opening of the bore 59, this filter being retained againstoutward movement by means of a threaded bushing 63. At its upper end,the valve member is sealed by means of an O-ring 64 retained by thebushing 65.

The uppermost end of the valve member is operatively connected with asolenoid actuator 66 which, upon being energized, will motivate thevalve 58 to a valve opened position against the action of spring 61.

Since in the engine of the present invention the ignition of combustiblemixture in the power cylinder 17 takes place after the piston has passedthrough its upper dead center position, it is not necessary that theignition means, such as a spark plug 67 shall be installed in the headof the cylinder. Accordingly, the spark plug can be mounted at the sideof the cylinder and arranged to be energized through a timingdistributor 68 of conventional construction driven by the power deliveryshaft 25. This is an advantage over the usual location in the head ofthe cylinder, which tends to restrict the size of the valve or valveswhich are mounted therein according to conventional practice.

While the enclosed embodiment shows the use of solenoid actuators forthe valves, it will be appreciated that in the broad concept of theinvention it is also possible to utilize mechanical actuators operatedfrom valve cam shafts according to conventional practice.

The utilization of solenoid actuators facilitates the timing of thevalve operations, which in this case is accomplished by means of a valvetimer switching means, as generally indicated at 69. This timercomprises three separate insulating discs 70, 71, and 72 which arefixedly secured to a common shafl, as indicated in phantom lines at 73,this shaft being synchronously driven from the power delivery shaft 25.In the position of these discs, as shown in FIG. 1, the disc 70 has aconducting strip 74 which extends from l80 in a clockwise direction tothe 360 point. The disc 71 has a conducting strip 75 which ex tends fromthe point in a clockwise direction to a 45 point. The disc 72 has aconducting strip 76 which extends from the 45 point in a clockwisedirection to a 225 point. Brushes 77, 78, and 79 are respectively shownfor the discs, these brushes being at the 0 position of each disc. Theconducting strips are connected to one side of an electric source 80a.The brush 77 connects with one terminal of solenoid actuator 47 througha conductor 80. Brush 78 connects with one terminal of solenoid actuator66 through a conductor 81, and the brush 79 connects with one terminalof the solenoid actuator 38 through a conductor 82. The other terminalsof the solenoid actuators are connected through a common conductor withthe other side of the electrical source as indicated at 80b. At therelative positions of the discs 70, 71, and 72, as just described above,it will be observed that the piston 26 is at the upper limit of itstravel and is in a dead center position, while the piston 19 at thispoint in timing is at a position going away from its dead centerposition, and wherein the crank pin 22 is at a 45 angle with respect tothe dead center position. This is a point at which the combustible fluidabove the piston 19 may be ignited, and at this position the crank armwill have an increased leverage as compared to substantially zeroleverage in conventional engines where the firing is accomplishedslightly before the piston reaches its dead center position. Because ofthis feature, greater power will be obtained from the power generatingpiston, than in the conventional type of engine.

With the clockwise rotation of the discs of the valve timer switchingmeans, it will be seen that the conducting strip 75 will have opened thevalve 58, when the piston 26 is moving towards its dead center position,and while the piston 19 is beginning to move away from its dead centerposition. Due to the different volume displacement of the piston 26 withrespect to the piston 19, a large volume under pressure of compressedcombustible fluid will be forced into the area above the piston 19 sothat when ignition takes place, full ad vantage may be taken of thepotential power developed by the combustion of the mixture. The timedrelation for opening of the intake and exhaust valves 42 and 33, as wellas the closing of these valves, will be accomplished by the conductingstrips 74 and 76 as the timer is operated.

From the foregoing description and drawings, it will be clearly evidentthat the delineated objects and features of the invention will beaccomplished.

Various modifications may suggest themselves to those skilled in the artwithout departing from the spirit of my invention, and, hence, I do notwish to be restricted to the specific forms shown or uses mentionedexcept to the extent indicated in the appended claims.

lclaim:

1. An engine comprising:

a. a crank case;

b. a first cylinder and a power delivery piston reciprocable therein;

0. means connecting said piston with a power delivery shaft, including aconnecting rod having one end connected to a crank on the shaft operablebetween dead center positions corresponding with the inner and outerlimits of travel of the piston in said cylinder;

d. a second cylinder and a piston operable from said power shaftreciprocable therein to provide a source of compressed combustiblefluid;

e. means operable to admit compressed combustible fluid from said sourceinto the first cylinder space above its piston to provide a sustainedpressure of combustible fluid therein during movement of the piston awayfrom its inner limit of travel to a predetermined ignition position andat which the crank will have substantially maximum turning leverage,comprising:

a valve controlled connection between said first and second cylindersfor conducting compressed combustible fluid from said second cylinder tosaid first cylinder, including a valve chamber having an end openinginto said crank case,

an elongated valve member slidably reciprocable in said valve chamberfor movements to valve closed and valve opened positions,

spring means normally urging said valve member to said closed position,and

means for actuating said valve member to said opened position, saidvalve member and spring being positioned to receive splash lubricationfrom the crank case through said chamber and opening;

f. means operable in timed relation to the power delivery pistonmovement for igniting the admitted combustible fluid at said ignitionposition of the piston; and

g. other means operable in timed relation to the power delivery pistonmovement for connecting the cylinder space above the piston with anexhaust flow passage for the products of combustion.

2. An engine according to claim 1, including filter means in said valvechamber positioned between said spring and the chamber end opening.

3. An engine according to claim 1, wherein the actuating means comprisesan electrically energizable solenoid.

4. An engine comprising:

a. a first cylinder and a power delivery piston reciprocable therein;

b. means connecting said piston with a power delivery shaft, including aconnecting rod having one end connected to a crank on the shaft operablebetween dead center positions corresponding with the inner and outerlimits of travel of the piston in said cylinder;

c. a second cylinder and a piston operable from said power shaftreciprocable therein to provide a source of compressed combustiblefluid;

d. means operable in timed relation to the movement of the piston insaid second cylinder for connecting the cylinder space thereabove withan intake flow passage for a combustible fluid;

e. an adjustable butterfly throttle valve for controlling said intakeflow passage;

f. means for adjustably limiting the extent of opening of the throttlevalve in accordance with changes in ambient atmospheric pressure;

g. means operable to admit compressed combustible fluid from said sourceinto the first cylinder space above its 7 8 piston to provide asustained pressure of combustible fluid at said ignition position of thepiston; and fluid movemen P 'y i. other means operabie in timed relationto the power piston away from its inner limit of travel to apredetermined ignition position and at which the crank will havesubstantially maximum turning leverage;

h. means operable in timed relation to the power delivery pistonmovement for igniting the admitted combustible delivery piston movementfor connecting the cylinder space above the piston with an exhaust flowpassage for the products of combustion.

1. An engine comprising: a. a crank case; b. a first cylinder and apower delivery piston reciprocable therein; c. means connecting saidpiston with a power delivery shaft, including a connecting rod havingone end connected to a crank on the shaft operable between dead centerpositions corresponding with the inner and outer limits of travel of thepiston in said cylinder; d. a second cylinder and a piston operable fromsaid power shaft reciprocable therein to provide a source of compressedcombustible fluid; e. means operable to admit compressed combustiblefluid from said source into the first cylinder space above its piston toprovide a sustained pressure of combustible fluid therein duringmovement of the piston away from its inner limit of travel to apredetermined ignition position and at which the crank will havesubstantially maximum turning leverage, comprising: a valve controlledconnection between said first and second cylinders for conductingcompressed combustible fluid from said second cylinder to said firstcylinder, including a valve chamber having an end opening into saidcrank case, an elongated valve member slidably reciprocable in saidvalvE chamber for movements to valve closed and valve opened positions,spring means normally urging said valve member to said closed position,and means for actuating said valve member to said opened position, saidvalve member and spring being positioned to receive splash lubricationfrom the crank case through said chamber and opening; f. means operablein timed relation to the power delivery piston movement for igniting theadmitted combustible fluid at said ignition position of the piston; andg. other means operable in timed relation to the power delivery pistonmovement for connecting the cylinder space above the piston with anexhaust flow passage for the products of combustion.
 2. An engineaccording to claim 1, including filter means in said valve chamberpositioned between said spring and the chamber end opening.
 3. An engineaccording to claim 1, wherein the actuating means comprises anelectrically energizable solenoid.
 4. An engine comprising: a. a firstcylinder and a power delivery piston reciprocable therein; b. meansconnecting said piston with a power delivery shaft, including aconnecting rod having one end connected to a crank on the shaft operablebetween dead center positions corresponding with the inner and outerlimits of travel of the piston in said cylinder; c. a second cylinderand a piston operable from said power shaft reciprocable therein toprovide a source of compressed combustible fluid; d. means operable intimed relation to the movement of the piston in said second cylinder forconnecting the cylinder space thereabove with an intake flow passage fora combustible fluid; e. an adjustable butterfly throttle valve forcontrolling said intake flow passage; f. means for adjustably limitingthe extent of opening of the throttle valve in accordance with changesin ambient atmospheric pressure; g. means operable to admit compressedcombustible fluid from said source into the first cylinder space aboveits piston to provide a sustained pressure of combustible fluid thereinduring movement of the power delivery piston away from its inner limitof travel to a predetermined ignition position and at which the crankwill have substantially maximum turning leverage; h. means operable intimed relation to the power delivery piston movement for igniting theadmitted combustible fluid at said ignition position of the piston; andi. other means operable in timed relation to the power delivery pistonmovement for connecting the cylinder space above the piston with anexhaust flow passage for the products of combustion.